1Scanf.Scanning(3)                OCaml library               Scanf.Scanning(3)
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NAME

6       Scanf.Scanning - no description
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Module

9       Module   Scanf.Scanning
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Documentation

12       Module Scanning
13        : sig end
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21       type in_channel
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24       The  notion  of input channel for the Scanf module: those channels pro‐
25       vide all the machinery necessary to read from any source of characters,
26       including  a  in_channel  value.   A Scanf.Scanning.in_channel value is
27       also called a formatted input channel or equivalently a  scanning  buf‐
28       fer.   The  type  Scanf.Scanning.scanbuf  below  is  an alias for Scan‐
29       ning.in_channel .
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32       Since 3.12.0
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35       type scanbuf = in_channel
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38       The type of scanning buffers. A scanning  buffer  is  the  source  from
39       which  a  formatted input function gets characters. The scanning buffer
40       holds the current state of the scan, plus a function to  get  the  next
41       char  from the input, and a token buffer to store the string matched so
42       far.
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44       Note: a scanning action may often require to examine one  character  in
45       advance;  when  this 'lookahead' character does not belong to the token
46       read, it is stored back in the scanning buffer  and  becomes  the  next
47       character yet to be read.
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51       val stdin : in_channel
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53       The  standard input notion for the Scanf module.  Scanning.stdin is the
54       Scanf.Scanning.in_channel formatted input channel attached to stdin .
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56       Note: in the interactive system, when input is read from  stdin  ,  the
57       newline  character that triggers evaluation is part of the input; thus,
58       the scanning specifications must properly skip this additional  newline
59       character (for instance, simply add a '\n' as the last character of the
60       format string).
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63       Since 3.12.0
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66       type file_name = string
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69       A convenient alias to designate a file name.
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72       Since 4.00.0
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76       val open_in : file_name -> in_channel
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79       Scanning.open_in fname returns  a  Scanf.Scanning.in_channel  formatted
80       input channel for bufferized reading in text mode from file fname .
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82       Note:  open_in returns a formatted input channel that efficiently reads
83       characters in large chunks; in  contrast,  from_channel  below  returns
84       formatted  input channels that must read one character at a time, lead‐
85       ing to a much slower scanning rate.
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88       Since 3.12.0
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92       val open_in_bin : file_name -> in_channel
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95       Scanning.open_in_bin fname returns a Scanf.Scanning.in_channel  format‐
96       ted input channel for bufferized reading in binary mode from file fname
97       .
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100       Since 3.12.0
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104       val close_in : in_channel -> unit
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106       Closes the in_channel associated with the given Scanf.Scanning.in_chan‐
107       nel formatted input channel.
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110       Since 3.12.0
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114       val from_file : file_name -> in_channel
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116       An alias for Scanf.Scanning.open_in above.
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120       val from_file_bin : string -> in_channel
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122       An alias for Scanf.Scanning.open_in_bin above.
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126       val from_string : string -> in_channel
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129       Scanning.from_string  s  returns  a Scanf.Scanning.in_channel formatted
130       input channel which reads from the given string.  Reading  starts  from
131       the  first  character in the string.  The end-of-input condition is set
132       when the end of the string is reached.
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136       val from_function : (unit -> char) -> in_channel
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139       Scanning.from_function f returns a Scanf.Scanning.in_channel  formatted
140       input channel with the given function as its reading method.
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142       When scanning needs one more character, the given function is called.
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144       When  the  function has no more character to provide, it must signal an
145       end-of-input condition by raising the exception End_of_file .
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149       val from_channel : in_channel -> in_channel
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152       Scanning.from_channel ic returns a Scanf.Scanning.in_channel  formatted
153       input  channel which reads from the regular in_channel input channel ic
154       argument.  Reading starts at current reading position of ic .
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158       val end_of_input : in_channel -> bool
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161       Scanning.end_of_input ic tests the end-of-input condition of the  given
162       Scanf.Scanning.in_channel formatted input channel.
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166       val beginning_of_input : in_channel -> bool
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169       Scanning.beginning_of_input  ic  tests the beginning of input condition
170       of the given Scanf.Scanning.in_channel formatted input channel.
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174       val name_of_input : in_channel -> string
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177       Scanning.name_of_input ic returns the name of the character source  for
178       the given Scanf.Scanning.in_channel formatted input channel.
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181       Since 3.09.0
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185       val stdib : in_channel
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187       A deprecated alias for Scanf.Scanning.stdin , the scanning buffer read‐
188       ing from stdin .
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194OCamldoc                          2020-09-01                 Scanf.Scanning(3)